Hi,
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Foul smelling vaginal discharge is suggestive of vaginal infection, cervical changes, seminal fluid infection (if occurs only after intercourse). The exact cause can only be made out after careful evaluation. Consider visiting your doctor/gynecologist at the earliest for thorough examination and further evaluation to look for the underlying cause for the symptoms that you describe. Vaginal swab/smear test done would help to rule out vaginal infection. PAP smear test done would help to rule out cervix related changes (erosion/dysplasia, pre-cancerous changes etc). Seminal fluid analysis done would help to rule out infection. Treatment as needed (based on examination findings and investigations results) would be started to help you. If infective cause gets detected, both you and your partner should get treated simultaneously to prevent re-infection. Be in regular monitoring and follow-up with your treating doctor/gynecologist and report any new/abnormal symptoms immediately. Drink plenty of water. Take adequate rest. Maintain healthy diet. Avoid vaginal douching, use of harsh soap or perfumes in the area. Use loose cotton undergarments and avoid use of tight fitting clothes.
Take care.